The electronic igniter circuit of U.S. Pat. No. 3,690,259 produces the firing of pyrotechnical charges, such as, for example, mines by the rupture of a bifilar line of a filmentary conductor of electrical current of small section having similar characteristics of use as those mechanically required for the manufacture of tripping apparatus.
In the most simple configurations such as those disclosed in U.S. Pat. No. 3,690,259 and in Frech Pat. No. 159,718 the necessary controls to insure the integrity of the element associated with the base circuit do not present the desired or necessary security before arming on the part of a qualified operator requiring a substantial number of operations which impose the need of non-negligible time and careful attention.
An object of the invention is to provide apparatus which satisfies all of the safety test requirements and has only a minimum number of operations. The indication of readiness is obtained in a substantially instantaneous manner. The electroexplosive apparatus can remain permeanently, during this control, in disarmed state.
The present invention is characterized essentially in that an appropriate voltage sensor associated with the adaptation elements is connected to the terminals of a condensor or energy reservoir included in the main circuit connecting the elements concurrently at the firing of the prior explosive, the said condensor being disposed in parallel in a line of the principal circuit comprising the feed source mounted in series with a resistance.